Transmitting system



Oct. ll, 1932. f l.. A. GEBHARD 1,882,074

TRANSMITTING SYSTEM Filed ngc. 22, 1928 Insulq-Hon .LOUIS A. GEIBHARD, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR TO WIRED n jg Patented Oct. 11, 1932 ETD TTES maar Arat

RADIO, INC., 0F NEW YORK, N. Y., A CORPORATION OF DELAWARE TRANSMITTING SYSTEM Application ed December 22, 192B. Serial No. 327,983.

the cooling system employed in thermionicV tube signaling systems.

Other and further objects of my invention will be apparent from the specification hereinafter following by reference to the accom-k panying drawing which diagrammatically shows the transmitting system of my inven- I tion.

high resistance in parallel with the source of anode potential where the negative termiinal is connected tothe cathode and ground.

The positive polarity of the source of anode potential is connected to theanode of the thermionic tube through a radio frequency choke coil. This radio frequencyV choke coil may have a comparatively low direct current or low frequency resistance while operating effectively as a. choke to the high frequency energy. When such an arrangement is employed, some high frequency energy will be present in the rubber insulating hose coil which conducts the circulating liquidto and from the thermionic tube. It is an object of my invention to exclude such high frequency energy from the insulating hose coil thereby preventing undue loss of energy and reducing the resistance to the potential supplied the anode. By excluding high frequency energy from the insulating hose coil, danger ofl high frequency potential break-down between adjacent turns of the coilis prevented.`

This potential break-down lin'the hose coil interrupts the circulation of the lcooling liquid and causes the entire system to be inoperative. In the transmitting system of my invention the foregoing disadvantages are overcome.

In the accompanying drawing, a source of signaling energy 1 is associated with a water cooled thermionic tube 2; Energy is transferred from source 1 to the grid connection 5 of thermionic tube 2 by means 'of capacity 6, Cathode connections Bare supplied with a source of energy from an alternating current supply 4 reducedV to the proper value by transformer 18. VThe electrical center of the cathode supply winding of transformer 18 is connected toY ground 10. High frequency inductance 12 is connected to thermionic tube receptacle 2a through capacity 11. Thermionic tube receptacle 2a is of the same potential as the anode potential of thermionic tube 2. ,y A source of energy 9a supplies the proper operating potential to grid connection 5 through resistance 7 and high frequency choke coil 8. A source 86:

of energy 9b is connected with the anode of thermionic tube 2 by means of metal tubing lll- 14a and receptacle 2a. A common connection 9 to ground 10 provides a cathode return circuit for sources of energy`9a and 85 9b. Coils of metaltubing 14 and 14a are provided as conductors for the circulating coling liquid to and from receptacle 2a.'V Coils 14 and 14a serve effectively as high frequency choke coils excludingl high fre- 90 quency energy from insulating hose coils 22-22ar and source of cooling liquid 21. Coilsv 14 and 14a have a low resistance to the supply of energy from source 9b tothe anode of thermionic tube 2 and aresuliicient 95 to offer a low resistance to the circulation of the cooling liquid. A capacity 16 is provided, conducting the low potential highr frequencyenergy to the ground or cathode-v circuit. Capacity 16 is a further protect-ion loo to prevent high frequency energy from reaching hose coils 22-22a and source 21, which may be omitted when coils 14 and 14a n are of the proper design.

It is obvious that any combination of coils may be employed in the cooling system. For

instance coil 14a may be omitted and coil 14y employed. In such an arrangement coil 14 could be of suitable reactance to prevent source of cooling liquid. A` connection 15is provided between the low potential ends of coils 14 and 14a thereby reducingv resistance to the supply of Lanode potential to thermionic tube 2 from source 9b. Coils 14 and 14a'1'nay be constructed of copper tubing or any suitable metal."V It is possible to connect the source ofganode potential to2@ providing'a suitable high frequency choke coil is -employed in series In the latter modification, coils 14 and v14aI neednot be of a low resistance'to the source of `anode potential. This allows considerable choice of vmetals and alloys thereof, that are effective high frequency choke coils but have a direct current resistance or low frequency resistance of too great avalue to be employed in the series arrangement 'heretofore mentioned. :When extremely high frequencies are employed it i; is obvious that coils 14 Vand 14a maybe of straight tubing and not formed in the coil arrangement illustrated in thev accompanying drawing. Aioad circuit-10, 12 and 13` is illustrated in the accompanying drawing. It is obvious that additional amplifiers may be employed of similar arrangement to that shownfin the accompanying drawing.

While Iv have described my invention in certain of its preferred embodiments, I desire that it be understood that modifications may be made and that no limitations upon my .invention are intended other than those imposed by the scope of the appended claims.-

WhatI claim as new and desire to secure by Letters Patent of the United State is as follows:

trodeofsaid thermionic tube for conducting 1 .A transmitting system employing thermionic tubes having the anode electrode cooled by a circulating liquid, a coil of metallic tubing connected with the anode electhe cooling liquidto the anode ofsaid tube while. excluding high frequency energy from Vthe source of said liquid and separate means connected with said tubing for dissipating heat from the cooling liquid.

2.; In' a Atransmitting system* employing thermionic tubes adapted to have the anodes` 5 source Of's'aid'circulatingliquid and separate cooling coils connected in series with said metallic tubing foriradiating heat from the circulating liquid.

3. In a transmitting system employing thermionic tubes having the anodes thereof cooled vby a circulating liquid, a coil of 1netallic tubing for conducting the circulating liquid to and from the anodes of said ther- 1 l mionic tubes said tubing having such dimenhigh frequency energy jfrom f` reachlng 'theArr sions las 'wijll offer a high Aeffective resistance to `high A'frequency `electrical energy while conducting `the anode potential to said tube and a heat dissipating coil connected with l.said coil of metallic tubing radiating heat from said circulating liquid.

4.1In 'a transmitting'V system employing thermionic tubes havingthe anodes thereof adapted tobecooled by a circulating liquid,

coils of metallic tubing for conducting the Vcirculating liquidrto and from said'thermionic tubes, said coils having a lhigh imped the anodes offsaid tubes,sa;id coils offering a low resistance to potentials supplied to said anodeswhile presenting a'high impedance to hi gh'frequency energy developed in circuits connected with said anodes and coils of insulation material connected in' series with said firstfmentioned coilsfor conveying cooling water thereto; y

V6'. In a transmitting system employing thermionic tubes, a thermionic tube having the anode thereof cooled'by a circulating liq- Y uid, coils of'tubing for conducting said liquidto the anode of said thermionic tube, said "coils having a low resistance to the circulation ofs'aid liquid and a high impedance to high frequency electrical energy existent on said anode, and auxiliary means connected with said coils of tubing for dissipating the' heat from VVsaid circulating liquid.

7 Ina transmitting system a thermionic tube having associated control and energ1zing circuits, means for cooling the anode of said tube by a circulation of liquid and a coil for conducting vthe cooling liquid to thel anode of said tubesaid coil having a low electrical resistance to low frequency and direct current venergy and a high impedance to high frequency signaling energy and a coil of insulation material connected with said' 8. In a transmitting system a thermionic tubehaving the anode thereof adapted to be cooled by a circulating liquid, a metallic conducting member for the circulating liquid, said member offering a low resistance to low frequency electrical energy and high impedance to electrical energy of high frequency and an insulated conducting member connected with said metallic conducting member and providing a path for the circulating liquid therethrough while radiating heat from the circulating liquid.

9. In a transmitting system employing thermionic tubes a high power thermionic tube having an anode adapted to be cooled by a circulating liquid, a conducting member for said liquid, said member having a low electrical resistance to direct current and a high impedance to high frequency signaling energy and an auxiliary conducting member connected with said aforementioned conducting member and having substantially infinite resistance to the passage of electrical energy while dissipating the heat from the circulating liquid.

l0. In a transmitting system employing thermionic tubes, a high power thermionic tube having an anode adapted to be fluid cooled, means for causing a cooling iuid to circulate to and from the anode of said thermionic tube, a member included in said means having a low resistance to the circulation of said liquid and electrical energy of low frequency value and having a high impedance to high frequency signaling energy and an auxiliary member connected with said means comprising tubing of insulating material having infinite resistance to electrical energy for dissipating the heat in said cooling fluid.

l1. A. transmitting system including a high power tube having a cathode, a control electrode and an anode, an oscillating circuit connected with said anode, a control circuit connected with said control electrode, means for energizing said cathode, a power supply circuit for said anode, a fluid circulating system for subjecting said anode to the effects of cooling fluid, said fluid circulating system including a supply pipe line and a discharge pipe line leading to said anode, a pair of independent sets of coils, one set of said coils consisting of metallic tubing wound in H the form of inductances with adjacent ends thereof connected to the power supply circuit for said anode for subjecting said anode to high potential through the circuit formed by the metallic tubing, the other set of said coils consisting of insulation material connected in series with said aforesaid coils for dissipating heat in the fluid path to said lforesaid coils while radio frequency currents from said oscillation circuit are prevented from reaching said Huid circulating system by the reactance oiiered by said first mentioned coils.

12. In a high power transmission system, a high power electron tube having an anode adapted to be cooled by a circulating fluid,

sets of independent pairs of coils, one set of said coils being formed by conductive tubing wound in the form of radio frequency choke coils and providing a circuitous path for the cooling fluid from said anode while conductively applying high potential to said anode, the other set of said coils being formed of insulation material, said coils conjointly isolating the source of iiuid supply from losses in said transmission system.

13. In a transmitting system including a high power tube having a cathode, a control electrode, and an anode adapted to be fluid cooled, an output coil connected with said anode, a control circuit connected with said control electrode, means for energizing said cathode, a source of power supply for said anode, a pair of metallic tubular coils having inductance of such value as to exclude radio frequency currents of the range of frequencies at which said transmitting system is operated, one of said metallic coils being f 

